[eng] This project which is named ¿Fundamental research of the combustion instability
of the lower heating value gas fueled engine¿ is supported by the National Science
Foundation of China.
This work has two big parts. ...[+]

[eng] This project which is named ¿Fundamental research of the combustion instability
of the lower heating value gas fueled engine¿ is supported by the National Science
Foundation of China.
This work has two big parts. One is the experimental research. The effects of the
LHV gases¿ composition (specially the effects of the non-hydrocarbon gases¿ fraction),
equivalence ratio, ignition parameters and engine conditions to the characteristic
parameters of the cycle-to-cycle variation are investigated. We also pay more attention to
the evolution process from the normal combustion to partial burning and misfire. Detection
of Ionic Current is another important way. Through comparing the characteristic of the
ionic current signal of different stage of the flame development, we can find the
relationship between the ionic concentration of the early combustion duration and the
engine work instability. Symbolic time series are used to establish the association between
the influencing factors and the characteristic parameters of the cyclic variation in order to
distinguish the main factors.
Another one is numerical simulation research. The cyclic variation model of the
engine combustion is built by using the theory of stochastic mathematics and nonlinear
dynamics. The multi-dimensional combustion model will be used to study the space-time
distribution of the flame of LHV gases¿ combustion. We can also establish the relationship
between the unevenness of the blends¿ parameters (composition, concentration,
temperature, etc) and the combustion instability.[-]